How to make ppb level concentration ?

Hi, I've N2 gas cylinder and 100 ppm NH3 gas cylinder. With these two cylinders, I'd like to make a ppb level (1- 100) concentration. Any idea how to do that?

01 February 2021 3,264 2 View

What will be the possible reasons to cause no bands on gel electrophoresis?

Hi, I am doing RNA extraction for my final year project. After extraction of RNA by using conventional method, I did quantification and qualification of RNA by using Nanodrop spec and gel...

11 January 2021 8,775 10 View

How to increase the attachment of the HEK293t cells to the glass coverslips or cell dishes?

Hey guys, I always have problems with the attachment of HEK293t cells to glass coverslips while doing IFA. They are so easy to detach from the coverslips while washing. The coverslips are already...

30 December 2020 8,381 3 View

Can anyone advise me on how to amplify V4 region of fecal DNA of dss-induced colitic mice for microbiota profiling?

Animals were fed DSS via drinking water and fecal samples were collected and DNA was isolated using Qiagen stool DNA isolation kit. The V4 region of extracted DNA was amplified with specific...

20 December 2020 1,739 3 View

Looking for a glass slide with very low Autofluorescence (GFP)?

Does anyone know any glass slides (thickness 0.1 to 1mm) that have very low autofluoresence (GFP). I am doing a very sensitive experiment that require my glass substrate to be as low fluoresence...

28 November 2020 1,917 6 View

Function of SDS in Northern Blot washing step?

In Northern blot, we normally use either 2*SSC+0.1% SDS or 0.1*SSC+0.1% SDS in washing step. Does anyone know what's the function of the SDS in the washing buffer? Thank you in advance

26 November 2020 2,432 1 View

How to calculate the analytical solution for the HYDRUS-3D model simulation of water and salt movement in soil?

Suppose an agricultural field with uniform soil texture and salinization. The groundwater depth is 20 meters, assuming that the depth of the groundwater and the concentration of salts remain...

25 November 2020 2,382 4 View

Protein concentration decrease after dialysis?

Recently I have been involved in this problem: After expressed by adding IPTG, lysed with B-PER, and resolved with Buffer B (8M urea), incubate with Ni-NTA beads, everything looks fine. When I...

21 November 2020 7,416 3 View

Recommend equipment of in vivo recording in mice brain?

Hello, I am trying to set up an in vivo recording system in mice brain. Which company do you recommend? Neuralynx? TDT? NeuroNexus? Which one do you guys use and why? Please let me know. Thank you!

12 November 2020 2,508 1 View

Looking for a method that aggregate Nano beads on demond?

I am working on a droplet based digital biosensing project. Assume I have some droplets (size 30-40um in diameter), each droplet contians aroun 10-20 Nano beads (100-300nm in diamter). The surface...

28 October 2020 5,761 7 View

Protein-aptamer gel electrophoresis help, please??

Hi, I have problems with running gel electrophoresis. I have tried agarose gel electrophoresis and native PAGE. I have two proteins, which have molecular weights of ~30kDa and ~180kDa and two...

03 March 2021 4,275 4 View

Gel electrophoresis result for total RNA samples, 1.5 Agarose gel was used, How to improve the integrity of RNA?

Gel electrophoresis, RNA degradation, RNA extraction from fresh tissue

02 March 2021 5,433 5 View

Problem with shRNA transfection. Why are only two plates getting contaminated instead of all?

I transfected my LNCaP-WT cells with 3 shRNA plus their NTC two weeks ago and split two puromycin selected cell plates on Friday last week(Feb 26). I checked for GFP in the cells, and they all...

28 February 2021 4,949 3 View

Any specific pipeline or parameter to analyse total transcriptomics study of brain tissue samples?

I have two groups of brain samples, control and treated for example. It was total RNA nova seq sequencing. I tried all the available pipeline like: star+rsem+deseq2, Hista+stringtie+cuffdiff,...

27 February 2021 356 6 View

Why is the efficiency of viral mRNA electroporation in PBMC low?

Hello, I have been struggling with the electroporation of PBMC with HIV-I mRNA. Although the quality of the RNA generated is good, and the handling of the cells in meticulous, the frequency of...

27 February 2021 9,233 3 View

What is the best concentration of cDNA to be used for qPCR?

I have synthesised cDNA from 500ng/ul of RNA. The concentration of the cDNA Is about 5000ng/ul. Should I dilute my cDNA or just use it as it is for my qPCR? I usually use 2ul of cDNA for a 20ul...

24 February 2021 8,618 3 View

Recommendations on homogenizers for RNA isolation?

I will be performing RNA isolation with frozen lung biopsy samples and am in the market for a tissue homogenizer. I am wanting a homogenizer that will fit in a 1.5ml tube. I was looking at the...

24 February 2021 3,623 3 View

RNA-seq DEGs downstream analysis and reporting in literature?

I used EdgeR to get the list of DEGs (differentially expressed genes) from my liver RNA-seq experiment. I have done the gene overrepresentation and GSEA based pathway analysis. I am currently...

23 February 2021 8,969 1 View

Is it efficient to do liquid biopsy to investigate the gene expressions of the tumor?

To do liquid biopsy and look for specific gene expressions there are so many published papers. Thera are different protocols and procedures used to isolate circulating cell free RNA or mRNA from...

23 February 2021 7,326 5 View

RNA degraded after good nanodrop readings?

23 February 2021 8,850 2 View